Things I Learned This Semester #29

Water, water, everywhere, right?  We're all taught that something like 70% of the surface of the Earth is covered in water.  And when you take a look at an image of our "blue planet" from space, it does look more "blue" than anything else.  But this stunning image puts a whole new perspective on it.  Or, at least, it did for me.

Earth, with all it's water locked up in a bunch of huge marbles.  Illustration by Jack Cook of Woods Hole Oceanographic Institute, from the USGS website.

The large blue sphere over the middle of the North American continent represents all of the water on Earth. Every molecule of H₂O, solid, liquid, or gas, in every living and non-living system.  The smaller sphere over Kentucky represents the portion ( around 2.5%) of that water that is actually fresh, the majority of which is underground and inaccessible to the life that relies on it.  The even smaller dot, the one over Atlanta, Georgia; that one represents the freshwater in all the rivers and lakes on the planet.  The water we most rely on.

As strange and interesting as it is to see Earth's water pulled off the globe and represented in this way, there is something else to take away from this image: water is precious.  In some parts of the world, people pay more for a gallon of water than they do for a gallon of gasoline.  In others, water shortages take a toll on the lives and livelihoods of many.  And even worse, in many places water is polluted with little regard of the consequences.  Having access to clean, drinkable water, right out of a tap, is something that many of us are so used to, we take it for granted.  But every drop counts, and protecting and conserving water is more important now than it has ever been.  As you can clearly see above, the "brown planet" is nowhere near as attractive as the "blue" one we all call home.